1. ## Trig question

If an earthquake has an intensity of x, then its magnitude, as compounded by the Richter Scale, is given by R(x) = log x/I sub 0, where I sub 0 is the intensity of a small measurable earthquake. (consider I sub 0 = 1 for this problem). If one earthquake has a magnitude of 4.4 on the richter scale and a second earthquake has the magnitude of 5.8 on the Richter scale, howe many times more intense (to the nearest whole number) is the second earthquake than the first?

A) 6
B) 15,848,931,925
C) 25
D) 21

2. Originally Posted by cspan1986
If an earthquake has an intensity of x, then its magnitude, as compounded by the Richter Scale, is given by R(x) = log x/I sub 0, where I sub 0 is the intensity of a small measurable earthquake. (consider I sub 0 = 1 for this problem). If one earthquake has a magnitude of 4.4 on the richter scale and a second earthquake has the magnitude of 5.8 on the Richter scale, howe many times more intense (to the nearest whole number) is the second earthquake than the first?

A) 6
B) 15,848,931,925
C) 25
D) 21
There is no need to put font tags around all options - it just makes it harder to read. Also this is a log problem - trig isn't involved

$R_{1} = log(x_1) \: \: \therefore \: x_1 = 10^{R_1}$

$R_2 = log(x_2) \: \: \therefore \: x_2 = 10^{R_2}$

Take the ratio of these

$\frac{x_2}{x_1} = \frac{10^{R_2}}{10^{R_1}}$

$R_2$ and $R_1$ are known and $\frac{x_2}{x_1}$ is the ratio of intensity (the answer you want)